Update 10/8

Radiation Pressure

Runs on Stampede2:

Running on 128 nodes (6144 cores), we currently (frame 211) have an efficiency of 13% hydro, 38% line transfer (including layout communications), 52% total. Estimated completion 2.9 days. This is down from 23%, 54%, 76% at frame 203 with estimated completion in 1.5 days, where the current run started. Reduced estimated wall time by a factor of ~10. Produced 8 frames in the last 6 hours.

Max speeds are only on the order of 10s, and haven't changed significantly in current run (nor has dt). Here are some comparisons of the mesh:

Frame 180 (pre-radiation pressure):

http://www.pas.rochester.edu/~adebrech/visit0020.png

http://www.pas.rochester.edu/~adebrech/visit0022.png

Frame 203:

http://www.pas.rochester.edu/~adebrech/visit0021.png

http://www.pas.rochester.edu/~adebrech/visit0023.png

Frame 211:

http://www.pas.rochester.edu/~adebrech/visit0025.png

http://www.pas.rochester.edu/~adebrech/visit0024.png

So it's definitely related to increased resolution due to disturbance by the radiation pressure, which should settle down eventually.

Pseudocode for AMR line transfer: 

Start line transfer
if (processor at -x boundary)
  calculate radiative transfer (to child boundaries?)    ! only actually needs to be calculated on finest grid
  if (hasChildren)
    prolongate at boundaries and send to child           ! somehow need to be traveling along the ray while we do this, so that we encounter children in order (so that prolongation and restriction are correct)
  end if
  send ray to neighbor
else
  receive from neighbor
  calculate radiative transfer
  if (hasChildren)
    prolongate at boundaries
  end if
  if (not at +x boundary)
    send to neighbor
  end if
end if

Related: Have we ever thought about using the MPI distributed graph routines to keep track of neighbors?

HD209458b

Discovered that there's something incorrect about the stellar size output by the code (because it's still set by the stellar lambda, since it's not needed on the grid). Rerunning postprocessing on BlueHive, should have some new results tomorrow morning.

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